<?

//====================================================
//                FileName:download.class.php
//                Summary: 文件下载类
//                Author: feifengxlq
//      Email:feifengxlq@sohu.com
//                CreateTime: 2005-7-19     
//                LastModifed:
//                copyright (c)2005 xlq.100steps.net  [email]feifengxlq@sohu.com[/email]
//   使用范例：
// $download=new download('php,exe,html',false);
//  if(!$download->downloadfile($filename))
//  {
//    echo $download->geterrormsg();
//  }      
//====================================================

class download{
  var $debug=true;
  var $errormsg='';
  var $Filter=array();
  var $filename='';
  var $mineType='text/plain';
  var $xlq_filetype=array();
 
  function download($fileFilter='',$isdebug=true)
  {
    $this->setFilter($fileFilter);
        $this->setdebug($isdebug);        
        $this->setfiletype();
  }
  
  function setFilter($fileFilter)
  {
    if(empty($fileFilter)) return ;
        $this->Filter=explode(',',strtolower($fileFilter));
  }
  function setdebug($debug)
  {
    $this->debug=$debug;
  }
  
  function setfilename($filename)
  {
    $this->filename=$filename;
  }
  
  function downloadfile($filename)
  {
    $this->setfilename($filename);
    if($this->filecheck())
        {
          $fn = array_pop( explode( '/', strtr( $this->filename, '', '/' ) ) );
          header( "Pragma: public" );
      header( "Expires: 0" ); // set expiration time
      header( "Cache-Component: must-revalidate, post-check=0, pre-check=0" );
          header( "Content-type:".$this->mineType );
      header( "Content-Length: " . filesize( $this->filename ) );
      header( "Content-Disposition: attachment; filename=".$fn );
      header( 'Content-Transfer-Encoding: binary' );
      readfile( $this->filename );
      return true;
        }else
        {
        return false;
        }
  }
  function geterrormsg()
  {
    return $this->errormsg;
  }
  
  function filecheck()
  {
    $filename=$this->filename;
        if(file_exists($filename))
        {
           $filetype=strtolower(array_pop(explode('.',$filename)));
           if(in_array($filetype,$this->Filter))
           {
             $this->errormsg.=$filename.'不允许下载！';
                 if($this->debug) exit($filename.'不允许下载！') ;
                 return false;
           }else
           {
             if ( function_exists( "mime_content_type" ) )
                 {
           $this->mineType = mime_content_type( $filename );
         }
                 if(empty($this->mineType))
                 {
                    if( isset($this->xlq_filetype[$filetype]) )  $this->mineType = $this->xlq_filetype[$filetype];
                 }
                 if(!empty($this->mineType))
                   return true;
                 else
                 {
                    $this->errormsg.='获取'.$filename.'文件类型时候发生错误，或者不存在预定文件类型内';
                        if($this->debug) exit('获取文件类型出错');
                        return false;
                 }
           } 
        }else
        {
          $this->errormsg.=$filename.'不存在!';
          if($this->debug) exit($filename.'不存在!') ;
          return false;
        }
  }
  
  function setfiletype()
  {
    $this->xlq_filetype['chm']='application/octet-stream';
    $this->xlq_filetype['ppt']='application/vnd.ms-powerpoint';
    $this->xlq_filetype['xls']='application/vnd.ms-excel';
    $this->xlq_filetype['doc']='application/msword';
    $this->xlq_filetype['exe']='application/octet-stream';
    $this->xlq_filetype['rar']='application/octet-stream';
    $this->xlq_filetype['js']="javascrīpt/js";
    $this->xlq_filetype['css']="text/css";
    $this->xlq_filetype['hqx']="application/mac-binhex40";
    $this->xlq_filetype['bin']="application/octet-stream";
    $this->xlq_filetype['oda']="application/oda";
    $this->xlq_filetype['pdf']="application/pdf";
    $this->xlq_filetype['ai']="application/postsrcipt";
    $this->xlq_filetype['eps']="application/postsrcipt";
    $this->xlq_filetype['es']="application/postsrcipt";
    $this->xlq_filetype['rtf']="application/rtf";
    $this->xlq_filetype['mif']="application/x-mif";
    $this->xlq_filetype['csh']="application/x-csh";
    $this->xlq_filetype['dvi']="application/x-dvi";
    $this->xlq_filetype['hdf']="application/x-hdf";
    $this->xlq_filetype['nc']="application/x-netcdf";
    $this->xlq_filetype['cdf']="application/x-netcdf";
    $this->xlq_filetype['latex']="application/x-latex";
    $this->xlq_filetype['ts']="application/x-troll-ts";
    $this->xlq_filetype['src']="application/x-wais-source";
    $this->xlq_filetype['zip']="application/zip";
    $this->xlq_filetype['bcpio']="application/x-bcpio";
    $this->xlq_filetype['cpio']="application/x-cpio";
    $this->xlq_filetype['gtar']="application/x-gtar";
    $this->xlq_filetype['shar']="application/x-shar";
    $this->xlq_filetype['sv4cpio']="application/x-sv4cpio";
    $this->xlq_filetype['sv4crc']="application/x-sv4crc";
    $this->xlq_filetype['tar']="application/x-tar";
    $this->xlq_filetype['ustar']="application/x-ustar";
    $this->xlq_filetype['man']="application/x-troff-man";
    $this->xlq_filetype['sh']="application/x-sh";
    $this->xlq_filetype['tcl']="application/x-tcl";
    $this->xlq_filetype['tex']="application/x-tex";
    $this->xlq_filetype['texi']="application/x-texinfo";
    $this->xlq_filetype['texinfo']="application/x-texinfo";
    $this->xlq_filetype['t']="application/x-troff";
    $this->xlq_filetype['tr']="application/x-troff";
    $this->xlq_filetype['roff']="application/x-troff";
    $this->xlq_filetype['shar']="application/x-shar";
    $this->xlq_filetype['me']="application/x-troll-me";
    $this->xlq_filetype['ts']="application/x-troll-ts";
    $this->xlq_filetype['gif']="image/gif";
    $this->xlq_filetype['jpeg']="image/pjpeg";
    $this->xlq_filetype['jpg']="image/pjpeg";
    $this->xlq_filetype['jpe']="image/pjpeg";
    $this->xlq_filetype['ras']="image/x-cmu-raster";
    $this->xlq_filetype['pbm']="image/x-portable-bitmap";
    $this->xlq_filetype['ppm']="image/x-portable-pixmap";
    $this->xlq_filetype['xbm']="image/x-xbitmap";
    $this->xlq_filetype['xwd']="image/x-xwindowdump";
    $this->xlq_filetype['ief']="image/ief";
    $this->xlq_filetype['tif']="image/tiff";
    $this->xlq_filetype['tiff']="image/tiff";
    $this->xlq_filetype['pnm']="image/x-portable-anymap";
    $this->xlq_filetype['pgm']="image/x-portable-graymap";
    $this->xlq_filetype['rgb']="image/x-rgb";
    $this->xlq_filetype['xpm']="image/x-xpixmap";
    $this->xlq_filetype['txt']="text/plain";
    $this->xlq_filetype['c']="text/plain";
    $this->xlq_filetype['cc']="text/plain";
    $this->xlq_filetype['h']="text/plain";
    $this->xlq_filetype['html']="text/html";
    $this->xlq_filetype['htm']="text/html";
    $this->xlq_filetype['htl']="text/html";
    $this->xlq_filetype['rtx']="text/richtext";
    $this->xlq_filetype['etx']="text/x-setext";
    $this->xlq_filetype['tsv']="text/tab-separated-values";
    $this->xlq_filetype['mpeg']="video/mpeg";
    $this->xlq_filetype['mpg']="video/mpeg";
    $this->xlq_filetype['mpe']="video/mpeg";
    $this->xlq_filetype['avi']="video/x-msvideo";
    $this->xlq_filetype['qt']="video/quicktime";
    $this->xlq_filetype['mov']="video/quicktime";
    $this->xlq_filetype['moov']="video/quicktime";
    $this->xlq_filetype['movie']="video/x-sgi-movie";
    $this->xlq_filetype['au']="audio/basic";
    $this->xlq_filetype['snd']="audio/basic";
    $this->xlq_filetype['wav']="audio/x-wav";
    $this->xlq_filetype['aif']="audio/x-aiff";
    $this->xlq_filetype['aiff']="audio/x-aiff";
    $this->xlq_filetype['aifc']="audio/x-aiff";
    $this->xlq_filetype['swf']="application/x-shockwave-flash";
  }
}
$filename=$_GET['filename'];
 $download=new download('php,exe',false);
  if(!$download->downloadfile($filename))
  {
    echo $download->geterrormsg();
  }  
?> 